Significant variation in P2Y 12 inhibitor use after peripheral vascular intervention in Medicare beneficiaries W. Schuyler Jones, MD, a,b Xiaojuan Mi, PhD, a Laura G. Qualls, MS, a Ryan S. Turley, MD, c Sreekanth Vemulapalli, MD, a,b Eric D. Peterson, MD, MPH, a,b Manesh R. Patel, MD, a,b and Lesley H. Curtis, PhD a,b Durham, NC Background There is no consensus regarding whether to use antithrombotic medications in patients with peripheral artery disease after lower-extremity peripheral vascular intervention. Objectives The main hypothesis is that significant variation exists regarding use of antithrombotic medications after lower-extremity peripheral vascular intervention. We sought to examine the patterns of postprocedural antithrombotic medication use and associated factors in Medicare patients. Methods We measured rates of P2Y 12 inhibitor use after peripheral vascular intervention in a 100% national sample of Medicare beneficiaries with Part D prescription drug coverage. We used logistic regression modeling to examine associations between patient and clinical factors and P2Y 12 inhibitor use. Results Between 2010 and 2012, a total of 85,830 patients underwent peripheral vascular intervention and had prescription drug claims. Overall, 18.3% of patients were treated with an oral anticoagulant, 19.1% received no P2Y 12 inhibitor, 30.8% received a P2Y 12 inhibitor before and after the procedure, 6.2% received a P2Y 12 inhibitor for up to 30 days after the procedure, and 25.6% received a P2Y 12 inhibitor for more than 30 days after the procedure. After adjustment, factors associated with P2Y 12 inhibitor use included male sex; black race; history of renal disease, dementia, or heart failure; physician specialty; and clinical setting of the procedure. We observed a strong interaction effect between clinical setting and physician specialty (P b .001). Conclusions One-fifth of patients who underwent lower-extremity peripheral vascular intervention did not fill a prescription for a P2Y 12 inhibitor. Patients whose operators were surgeons or radiologists had lower odds of P2Y 12 inhibitor use. More research to determine the optimal use and duration of antithrombotic medications after the procedure is warranted. (Am Heart J 2016;179:10-18.) Lower-extremity peripheral artery disease (PAD) is a prevalent condition that affects more than 8 million people in the United States. 1,2 Patients with PAD are at greater risk for cardiovascular events, lower-extremity amputation, and death. 1,3,4 Clinical practice guidelines recommend that all patients with symptomatic PAD be treated with cardioprotective medication, such as anti- platelet agents and statins. 2,5-7 Even with medical treatment, patients with PAD often remain symptomatic and undergo lower-extremity peripheral vascular inter- vention for symptom improvement or limb salvage. Once a decision has been made to perform peripheral vascular intervention, clinicians must choose which antithrombotic medications to use and the duration of therapy after the procedure. The available options include antiplatelet monotherapy (eg, aspirin or clopido- grel), dual antiplatelet therapy (eg, aspirin and clopido- grel), or oral anticoagulation. There is a relative dearth of evidence regarding optimal antithrombotic therapy after From the a Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, b Duke Clinical Research Institute and Department of Medicine, Duke University School of Medicine, Durham, NC, and c Duke Clinical Research Institute and Department of Surgery, Duke University School of Medicine, Durham, NC. Financial Disclosures: Dr Jones reported receiving research grants from AstraZeneca and Boston Scientific and serving as a consultant for the American College of Radiology. Dr Vemulapalli reported receiving research grants from Boston Scientific. Dr Peterson has received research grants from American College of Cardiology, American Heart Association, Eli Lilly & Co, Janssen Pharmaceutical Products, Society of Thoracic Surgeons; and serves as a consultant/on the advisory board for AstraZeneca, Bayer AG, Boehringer Ingelheim, Janssen Pharmaceutical Products, Merck & Co., and Sanofi. Dr Patel reported receiving research grants from Astra Zeneca, Johnson & Johnson, and Pluristem; and serving as a consultant for Baxter, Bayer, Genzyme, and Ortho McNeil Jansen. Funding Source: This project was funded by American Heart Association Clinical and Mentored Population Science Research Grant #14CRP18630003 awarded to Dr Jones. Deepak L. Bhatt, MD, MPH served as guest editor for this article. Submitted December 6, 2015; accepted June 8, 2016. Reprint requests: W. Schuyler Jones, MD, Duke University Medical Center, Box 3126, Durham, NC 27710. E-mail: schuyler.jones@duke.edu 0002-8703 © 2016 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ahj.2016.06.002 Clinical Investigation